FIG. 1 illustrates a block diagram of a point of sale system 10 developed and marketed by the Assignee in the petroleum industry. The point of sale system has a master console 12 and a slave console 14 which have an identical architecture. The master console 12 includes a processor, not illustrated, which controls the slave console. The slave console 14 also includes a processor. The master console 12 and the slave console 14 provide a fuel dispensing station with two consoles each of which contains a keyboard 16, a cash drawer 18 and an operator display 20. The master console also controls one or more fuel dispensers 22 which are used by customers of the fuel dispensing station to purchase fuel. The keyboards 16, cash drawers 18 and operator displays 20 function in conjunction with the master console 12 and the slave console 14 to control the collection of money associated with the sale of petroleum products as recorded by the dispensers 22 and process and display information pertaining to the sale of the petroleum products. As indicated in parenthesis, the Assignee's product designation for systems of this configuration is TCRG.
The prior art system 10 of FIG. 1 has distinct disadvantages. First, its architecture only permits the implementation of two consoles. In large fuel dispensing stations it is necessary to have more than two consoles to completely service the customer base which is purchasing fuel from a large number of fuel dispensers 22 which requires additional master-slave console pairs to be installed. Furthermore, in addition to having a limited number of consoles, the overall cost of the system is high because both the master console and slave console contain the same hardware which, when in use, has the on-board control function of the slave console disabled, thereby adding the expense of processing hardware to the system which is not used. The overall system 10 is controlled only by the processor resident in the master console 12.
FIG. 2 illustrates a point of sale system 30 which was developed in the petroleum industry subsequent to the point of sale system 10 illustrated in FIG. 1. The point of sale system 30 is controlled by a controller 32 which contains a host processor controlling the overall functioning of the system. The controller 30 controls the overall operation of fuel dispensers 22, communications to and from a credit network 34, communications to and from a tank monitor 36 which monitor the level of fuel in the various tanks associated with the fuel dispensing station and other equipment 38 which is diverse in design and depends upon the particular fuel dispensing station functionality. It should be noted that the dispenser 22, credit network 34, tank monitor 36 and other equipment 38 are connected to the controller 32 by serial communications links 60. The dispensers 22, credit network 34, tank monitor 36 and other equipment 38 function as peripheral devices of the processor resident in the controller 32.
The site controller 32 is connected by a serial communications link 60 to at least one peripheral operator console 40. The number of peripheral operator consoles is variable. The Assignee's version of this system, which was marketed under the trademark G-SITE.TM., has up to four peripheral operator consoles 40. Each operator console 40 includes a processor which controls a plurality of peripheral devices which include a personal identification number pad 42, a card reader 44, for reading the magnetic stripe associated with a credit card used for the purchasing of products, a keyboard 46, a cash drawer 48, and a customer display 50. All of these peripheral devices are well known in their use with point of sale systems such as those in the petroleum industry.
The prior art system of FIG. 2 has disadvantages. First, every operator console 40 includes its own microprocessor control which requires a housing and power supply which adds to the overall cost of the system. The primary disadvantage of the system 30 of FIG. 2 is that, even for systems having a single operator console, it is necessary to have at least two separate computer systems with the first computer system being resident in the site controller 32 for controlling the dispensers 22, credit network 34, tank monitor 36 and other equipment 38 and the one or more additional computer systems resident in each of the operator consoles 40 which are required to control the pin pad 42, card reader 44, keyboard 46 cash drawer 48 and customer display 50, as peripheral devices to the processor in each operator console. Furthermore, this system has an additional disadvantage of requiring additional counterspace because the housing for each of the operator consoles 40 is separate from that of the site controller 32. In point of sale systems, such as in fuel dispensing stations, counterspace is extremely valuable and hard to obtain. Any reduction in physical size of the hardware required to implement a system including required counterspace provides a distinct marketing advantage to influence customers to purchase the system if they do not have unlimited valuable and scarce counterspace. In summary, the system 30 of FIG. 2 suffers from having a relative high cost which is sufficiently high to influence sales to operators of petroleum stations and is physically large enough in size to make its installation a potential problem in stations not having unlimited counterspace.